… is the process of cumulative material degradation with repeated loading – is often described chronologically in micromechanical terms as “initiation” – creating a crack – followed by crack propagation, modeled mathematically using fracture mechanics.

… are laboratory tests to determine cycles-to-failure that are stopped before the specimen fails. These suspended tests do not contain the same statistical information as tests to failure do. Here’s how to analyze them correctly.

(NDE) Since the cracksize is unknown, it is often assumed to be a size large enough to grow, but small enough to be missed by inspection. Thus, the quality of the life prediction depends on measuring the effectiveness on the NDE.